• 한국식품과학회지
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• 제4권3호
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• pp.213-223
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• 1972

This paper chose the methods of methylesterification of the use of methoxide, the mixture solution of methanol-benzen-sulfuric acid in transesterification of the fat in cow's milk and modified powder milk and separated by gas liquid chromatography with F.F.A.P., D.E.G.A. as liquid phase. Quantitative analysis of the fatty acid of milk fat in cow's milk and modified powder milk was determined by gas liquid chromatography using the method of temperature programming which should be used to obtain satisfactory separation of short chain fatty acid on the chromatogram. It was found that the fatty acid composition of cow's milk and modified powder milk are all the major fatty acid of milk fat obtained by GLC analysis. Main components was found to be from butyric acid to arachidonic acid showing Fig. 3, 4, 5 and Table 4, 5, 6, 7, 8, 9.

• 한국식품과학회지
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• 제28권2호
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• pp.298-304
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• 1996

참기름의 품질을 고소한 냄새, 탄 냄새, 전체적 인 품질 만족도의 세 항목으로 관능 평가하고 상온에서 휘발성 성분을 포집하여 정량 분석하였다 그리고 세 항목의 관능특성 변화에 가장 밀접한 휘발성 성분을 파악하고자 단계적 분별 분석을 실시하였으며 선정된 5개 peaks의 중요도를 정준 분별 분석, 분별 분석 그리고 주성분 분석으로 검토하였다. 5개 peaks 중에서도 가장 중요한 휘발성 성분은 2,5-dimethylpyrazine과 2-methylpyrazine이었으며 각각 고소한 냄새 및 탄 냄새의 척도로 적용할 수 있었다 관능적으로 좋은 품질의 참기름은 2,5-dimethylpyrazine과 2-methylpyrazine의 함량이 각각 $35.82{\sim}4.43$ppm,\;28.90{\sim}6.35ppm$인 것으로 밝혀졌다.

• Molecules and Cells
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• 제37권3호
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• pp.248-256
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• 2014

N-acetylglucosamine kinase (GlcNAc kinase or NAGK; EC 2.7.1.59) is a N-acetylhexosamine kinase that belong to the sugar kinase/heat shock protein 70/actin superfamily. In this study, we investigated both the expression and function of NAGK in neurons. Immunohistochemistry of rat brain sections showed that NAGK was expressed at high levels in neurons but at low levels in astrocytes. Immunocytochemistry of rat hippocampal dissociate cultures confirmed these findings and showed that NAGK was also expressed at low levels in oligodendrocytes. Furthermore, several NAGK clusters were observed in the nucleoplasm of both neuron and glia. The overexpression of EGFP- or RFP (DsRed2)-tagged NAGK in rat hippocampal neurons (DIV 5-9) increased the complexity of dendritic architecture by increasing the numbers of primary dendrites and dendritic branches. In contrast, knockdown of NAGK by shRNA resulted in dendrite degeneration, and this was prevented by the co-expression of RFP-tagged NAGK. These results suggest that the upregulation of dendritic complexity is a non-canonical function of NAGK.

• 약학회지
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• 제44권2호
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• pp.197-203
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• 2000

The enzymatic properties of $\beta$-galactosidases from Aspergillus oryzae, bovine liver and Saccharomyces pragilis have been studied using enzyme-linked lectin assay based on the RC $A_{120}$ and BS-II lectins which specifically bind to terminal galactose and GlcNAc residue, respectively. Asialofetuin, a monomeric glycoprotein with approximately 48 kDa in molecular weight, was used as a substrate. This glycoprotein contains three N-linked triantennary complex type carbohydrate chains with each of which terminating in Ga1$\beta$P1 longrightarrow4G1cNAc (74%). Their optimal pHs were 3.5 and 6.5 (A. oryzae), and 3.5~5.5 (bovine liver and S. fragilis) at 37$^{\circ}C$ during 24 hrs, and the effective concentrations were 0.9, 2.9, and 1.7 mg/ml, respectively The enzyme from A oryzae requires 100 mM N $a^{+}$ or $K^{+}$, while the enzyme from bovine liver requires $Ba^{2+}$ for activity. However all of the three $\beta$-galactosidases were inactivated by SDS and C $u^{2+}$. These results indicate that the hydrolysis of glycoprotein such as asialofetuin depends on the reaction conditions of $\beta$-galactosidases and some metal ions. ions.

• Journal of Life Science
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• 제10권1호
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• pp.51-56
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• 2000

In many cases of human cancer, the appearance of hypersialylated glycan structures is related to a precise stage of the disease ; this may depend on the elebated sialyltransferase activity during carcinogenesis. The aim of this study was to investigate the inhibitory effects of Oriental medicinal herbs on enzymatic activities of two kinds ofsialyltransferase, Gal $\beta$ 1,3GalNAc$\alpha$2,3-sialyltransferase(ST3Gal I) and Gal $\beta$ 1,4GlcNAc $\alpha$2,6-sialyltransterases(ST6Gal I), which are well known as glycosyltransterases associated with cancer. The aqueous extracts of Scutellaria Baicalensis Georgi, Coptidis Rhizoma, Glycyrrhiza urlensis Fisch, Bupleuri Radix and Platycodi Radix were prepared and tested, respectively. At concentration of 100$\mu$g, Glycyrrhiza uralensis Fisch showed the highest inhibitory effects(about 42% and 57%, respectively) on ST3Gal Iand ST6Gal Iactivities. ST3GAl I was inhibited about 23% by Scutellaria baicalensi G댁햐, but not by the other samples, whereas ST6Gal I was inhibited about 20% and 40%,respectively, by Scutellaria baicalensis Georgi and Bupleuri Radix. All inhibitory effects were obtained in a concentration-dependent manner.

• Journal of Microbiology and Biotechnology
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• 제18권4호
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• pp.759-766
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• 2008

Among more than a hundred colonies of fungi isolated from soil samples, DY-52 has been screened as an extracellular chitin deacetylase (CDA) producer. The isolate was further identified as Mortierella sp., based on the morphological properties and the nucleotide sequence of its 18S rRNA gene. The fungus exhibited maximal growth in yeast peptone glucose (YPD) liquid medium containing 2% of glucose at pH 5.0 and $28^{\circ}C$ with 150 rpm. The CDA activity of DY-52 was maximal (20 U/mg) on the 3rd day of culture in the same medium. The CDA was inducible by addition of glucose and chitin. The enzyme contained two isoforms of molecular mass 50 kDa and 59 kDa. This enzyme showed a maximal activity at pH 5.5 and $60^{\circ}C$. In addition, it had a pH stability range of 4.5-8.0 and a temperature stability range of $4-40^{\circ}C$. The enzyme was enhanced in the presence of $Co^{2+}$ and $Ca^{2+}$. Among various substrates tested, WSCT-50 (water-soluble chitin, degree of deacetylation 50%), glycol chitin, and crab chitosan (DD 71-88%) were deacetylated. Moreover, the CDA can handle N-acetylglucosamine oligomers $(GlcNAc)_{2-7}$.

• 대한화학회지
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• 제29권5호
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• pp.496-502
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• 1985

농산물에 잔류되어 있는 16종의 유기염소제 농약들을 기체-액체 크로마토그래피(GLC)로 동시에 정량하기 위하여 필요한 전처리 과정인 용매추출과 불순물 제거(Cleanup) 처리에 대하여 조사 검토 하였다. 농산물로 부터 농약들을 $H_3PO_4$와 물을 가한 강산성(pH 1.5이하)의 actone용액으로 녹여낸 다음, petroleum ether를 분배 용매로 사용하여 농약을 추출시켰다. 추출물에서 용매를 증발시켜 날려보내고 ethylether-petroleum ether (6 : 94) 용리액으로 녹여서 650$^{\circ}$C에서 활성화 시킨 Florisil관을 통과시켜 불순물을 제거 하였다. Petroleum ether에 의한 추출효과는 94%이상으로 AOAC법 보다는 우수 하였고, Florisil관 크로마토그래피법에 의해 불순물이 제거되었다.

• 대한화학회지
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• 제42권5호
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• pp.549-558
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• 1998

Campylobacter jejuni 그램 음성균의 O-antigen 부위를 구성하는 반복 단위 삼탄당 합성의 주요 중간체인 이당류들을 글루코스아민 주게와 갈락토스 받게를 ${\beta}(1{\rightarrow}3)$ 클리코시드 결합으로 연결함으로서 합성하였댜. 이들의 합성 과정에서 갈락토스 당 부위의 2, 3, 4 번 OH기들의 글루코스아민 받게에 대한 높은 위치선택성이 발견되었으며 이를 이용하여 2, 4번 OH에 대한 선택적 보호과정을 생략할 수 있었고 결과적으로 합성과정을 단축시킬 수 있었다.

• 한국식품과학회지
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• 제12권1호
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• pp.6-12
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• 1980

한국산(韓國産) 목이(木耳) 석의중(石衣中) 지방산(脂肪酸) 조성(組成)과 스테롤 성분(成分)의 구명(究明)을 G.L.C.와 I.R. 분석(分析)에 의하여 검토(檢討)한 결과(結果) 다음과 같은 결과(結果)를 얻었다. G.L.C에 의(依)한 지방산(脂肪酸의 조성(組成)은 목이(木耳)의 경우 linoleic acid 33.73, palmitic acid 15.52, stearic acid 5.03, oleic acid 16.03, linolenic acid 17.80 및 미지산(未知酸) 11.89%를 나타낸 반면(反面), 석의(石衣)는 linoleix acid 46.35, palmitic acid 31.71, oleic acid 16.82, 미지산(未知酸) 5.12% 및 소량(小量)의 stearic acid와 linolenic acid를 보여주었다. 스테롤 성분(成分)을 T.L.C.에 의(依)하여 분리(分離)한 후(後) I.R. 분석(分析)으로 구명(究明)한 결과(結果) 목이(木耳)와 석의(石衣) 모두 sitosterol과 ergosterol을 함유(含有) 하였다.

• 한국식품영양과학회지
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• 제11권3호
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• pp.75-79
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• 1982

한국산(韓國産) 녹두(綠豆)(Phaseolus aureus)의 성숙단계별(成熟段階別) 지방산(脂肪酸)의 함량변화(含量變化)를 구명(究明)하기 위하여 개화후(開花後) 10일(日), 15일(日), 20日, 25일(日), 30일(日)의 5단계(段階)로 채취하여 분석(分析)한 결과(結果)를 요약(要約)하면 다음과 같다. (1) 조지방(粗脂肪)의 함량(含量)은 숙성(成熟)이 진행됨에 따라 증가(增加)하였다. (2) 녹두(綠豆)의 성숙과정중(成熟過程中) 나타나는 지방산(脂肪酸)은 myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid 및 linolenic acid 등이다. (3) myristic acid, palmitic acid는 성분(成熟) 이후에서는 거의 나타나지 않았다. (4) 총(總) 지방산중(脂肪酸中) linoleic acid 함량이 가장 많고 oleic acid, linolenic acid는 거의 비슷한 함량(含量)을 보였다. (5) 성숙과정중(成熟過程中) 포화지방산(飽和脂肪酸) 대(對) 불포화지방산(不飽和脂肪酸)은 16-19/81-84%의 비율(比率)로 함유(含有)되어 있음을 알 수 있었다.